The invention relates to a rim-fire cartridge and to a process for producing a rim-free cartridge.
A rim-fire cartridge according to the prior art is shown in FIG. 1. A cartridge case 2 has on its base 3 a radial bulge 10, into which is placed an ignition charge 1. The cartridge case 2 is filled with propellent-charge powder 11 and the propellent-charge container 2 is closed with a projectile 12. Known ignition charges 1 contain heavy metals and are very sensitive to impact and friction, which means that even in the case of a low striking-pin energy, the known rim-fire cartridges ensure a uniform and complete reaction of the ignition charge in a comparatively short ignition time txe2x89xa61 ms.
In comparison with the known pollutant-containing ignition charges, modern environment-friendly ignition charges are less sensitive to friction and impact and in connection with the known rim-fire cartridges can, when fired, result in very long ignition times or even ignition failure.
The underlying objection of the invention is to improve a rim-fire cartridge and a process for producing a rim-fire cartridge in such a way that even with low-pollutant ignition charges and low striking-pin energy, a complete and uniform reaction of the ignition charge in short ignition times is ensured, so that ignition failures do not occur.
This object is met with respect to the rim-fire cartridge in accordance with the invention as a result of the fact that the base of the cartridge case is pressed inwards at least in partial regions, and as a result of this, the opening of the bulge towards the inside of the cartridge case is reduced.
As a result of this and in contrast with the prior art, the ignition charge is dammed, as a result of which the reaction of the ignition charge at the start of the reaction phase is optimised. As a result of this measure, a uniform and complete reaction of the ignition charge in short ignition times is achieved, so that ignition failures do not occur.
In a preferred embodiment, the base is pressed inwards in the axial direction to the extent of the inside diameter of the cartridge case. As a result of this, the striking-pin energy is used exclusively to deform the bulge, or in other words to deform the charge slot in which the ignition charge is located, and does not have to undergo any losses for the base deformation in the centre of the base of the cartridge case. As a result of this, the ignition sensitivity is substantially improved.
In a further advantageous improvement, the bulge is re-pressed after the ignition charge has been put in, and as a consequence, the ignition charge is compressed. As a result of this, the reaction of the ignition charge is improved. In certain cases, depending on the choice of ignition charge, this compression or re-pressing of the bulge can even be dispensed with.
In one embodiment, the compression or re-pressing of the bulge takes place with a tool having flat pressing faces, for example a combination pliers. As a result of this, the bulge has a more rectangular cross-section.
An alternative advantageous embodiment is distinguished as a result of the fact that the bulge is re-pressed with a sharp-edged tool, with only the region of the bulge that adjoins the cartridge case being re-pressed. As a result of this, the bulge has a more droplet-shaped cross-section.
Alternatively, the object with respect to the process for producing a rim-fire cartridge is achieved as a result of the fact that before the ignition charge is introduced, the base of the cartridge case is pressed inwards at least in partial areas, and as a result of this, the opening of the bulge towards the inside of the cartridge case is reduced.
Advantageously, the base of the cartridge case is pressed inwards in the axial direction to the extent of the inside diameter of the cartridge case. The advantages of these process claims are identical to those of the device claims.
Advantageously, after the ignition charge has been introduced, the bulge is re-pressed for the purpose of compression. In one embodiment, this takes place with a tool having flat pressing faces, and in another embodiment with a sharp-edged tool, in which case only the region of the bulge that adjoins the cartridge case is pressed in.